Aspirating cartridge syringe



July 21,1959 9. REZNEK 2,s9s;473

- ASPIRATING CARTRIDGE SYRINGE Filed July 12, 1954 INVENTOR I f- SOLOMON REZNEK ATTORNEY United States Patent {Ofiice ASPIRATING CARTRIDGE SYRINGE Solomon Reznek, Wheeling, W. Va., assignor to Cook- Waite Laboratories, Inc., New York, N.Y., a corporation of Delaware This invention relates to a new and improved syringe which utilizes a disposable cartridge for the material to be injected and this invention is directed to this type of syringe including means for aspirating, the present invention being directed to the structure of the syringe itself and also in combination with a novel cartridge plunger construction cooperating therewith for providing the aspirating effect. 2

There are two main types of syringes, the Luer, or medical syringe, and on the other hand the dental syringe. This invention relates to the dental syringe. It has been found that in many cases of use of the dental syringe, the dentist may hit a vein, and the consequent injection of the local anesthetic is at least partially intravenous, resulting in undesirable side reactions and loss of anesthetic efliciency, so that aspiration is of considerable importance. V i

In the present case, an object of the invention resides in the provision of a syringe of the so-called dental type using a disposable cartridge having a plunger wholly of rubber, and including inter-engaging means between the plunger rod for the syringe and the rubber plunger of the ampoule cartridge, whereby the latter may bepositively engaged and slightly retracted by the plunger rod for the aspiration prior to injection. y

Further objects of the invention include the provision of a new and improved ampoule cartridge of decreased cost which is very easily disengaged from the syringe plunger rod when the injection is finished and wherein the syringe itself is interchangeably usable whether the standard or the novel aspirating plunger is used; and in addition, the invention provides against the staining by corrosion of metal inserts of adjacent cartridges, etc. during storage.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings, in which Fig. 1 is a view in side elevation of a device according to the present invention, parts being in section;

Fig. 2 is an enlarged section on line 22 of Fig. 1; I

Figs. 3 and 4 are sections on respective lines 33 and 44 in Fig. 2;

Fig. 5 is a view similar to Fig. 2 but showing the syringe plunger disengaged from the plunger of the cartridge and a modified actuating structure; and

Fig. 6 is a section on line 66 of Fig. 5.

The syringe used as illustrative of the present invention includes a barrel 10 which may be provided with one or more windows or openings 12; a hypodermic needle 14 for conducting the contents of a disposable ampoule cartridge 16 in the barrel 10 through a cartridge piercing inner needle end 18 located in the tip of the barrel as shown in Fig. 1; and a plunger rod 20 for exerting pressure upon the content of the cartridge to expel the same through the needle.

The cartridge 16 is provided with a plunger 22 and normally the inner end ofthe plunger rod 20 merely engages the cartridge plunger and exerts pressure to move the same along in the cartridge to expel the contents of the cartridge as stated. In the prior art, however, there can be no aspirating by means of the needle 14, and the only possible action is to press the plunger for instance to the right in Figs. 1 and 2. The cartridge plunger cannot be withdrawn or moved to the left. Of course when the cartridge has been used, it is thrown away and another cartridge is placed in the syringe.

Loosening of the rotary locking sleeve 24 in a manher well known in the art to allow pivoting of the hinged head .26, provides for opening the breech end of the barrel 10 for the extraction of a spent cartridge and insertion of a new cartridge without interference from the plunger rod or the hinged head 26. The head 26 may be provided with the usual finger-bar 28.

In the present case,the invention provides an integrally molded, distortable rubber tip on the cartridge plunger 22, as clearly shown at 30 in Fig. 2, this rubber tip extending or at least facing to the exterior of the cartridge 16 in storage.

In addition, for cooperation with this rubber tip there is provided a gripping member generally indicated at 32 in Fig. 2, and attached to the plunger rod 20 or the like at the inner end thereof as respects the barrel 10. Member 32 is provided with a series of resilient gripping fingers 34 provided with serrations 36 at the interior thereof, the fingers being arranged generally radially (see Fig. 3) and designed to be radially compressed to be brought toward each other to firmly grip the rubber tip30.

The means provided for causing the gripping fingers to move radially toward each other to grip the rubber tip may take the form of an exterior barrel or sleeve indicated at 38. This barrel may be rotatable relative to the gripping fingers and member 32, and if desired, may be provided with inter-engaging threads 40 for providing relative longitudinal motion between gripping fingers 34 and the actuating sleeve 38 in order to cause the fingers 34 to move inwardly relative to each other. The exterior surfaces of the gripping fingers extend radially outwardly past the internal diameter of sleeve 38 in normal extended condition, and the sleeve 38 acts in the nature of a cam to compress the fingers upon the required relative axial motion thereof.

The sleeve 38 may be extended as at 42 and may be knurled at this end as at 44 and it may extend outwardly of the knurled locking sleeve 24 for convenience in operation, (see Fig. 1).

After inserting the cartridge 16 in the barrel in the usual manner, the hinged head 26 is replaced in its operative position axially aligned with barrel 10. The locking sleeve 24 is then turned up to lock the parts in position in the usual manner.

The knurled end 44 of sleeve 42 may then be turned relative to plunger rod 20, which is held by one hand while sleeve 42 is rotated by the fingers of the other hand, so that with the inner end of the plunger rod in engagement with plunger 22, gripping fingers 34 will move radially inwardly and firmly grip the rubber tip 30, so that the plunger 22 and plunger rod 20 will move together in either direction. The act of aspiration then becomes simple and clearly apparent to those skilled in the art, since merely by withdrawing slightly on plunger rod 20, as for instance by means of the thumb-piece 46 thereon, blood from any vein pierced by needle 14 will be withdrawn and the piercing of the vein will then be apparent to the operator.

A modification is shown in Fig. 5 wherein the fingers are illustrated as retracted, and the plunger 22 is free.

i Patented July 21, 1959 The grippingfingw.aqtuatorrbarrel 42 instead of being rotatable within the locking sleeye 24, is axially slida y keyed thereto as by slot 48 and key 50, so that when the hinged head 26 is placed operable alignment with ar l 1.0, h o kin sle ve 4...- 1 9 b n r a e 9 lock the cartridge in j position als rotates the gripper finger; actuating sleeve 42 relativeto, the plunger rod 20", thus accomplishing tyvo. actions, that of locking the hinged head 26 as usual, andalso of causing gripper fingers 34 to be moved radially inwardly to firmly engage and grip the rubber tip 30. In this. case, the key' is provided with a tightfit interiorly of the locking sleeve 24 and with a loose fit with reference to keyway 48 to pro} vide for axial sliding of the sleeve 42 relative to locking, sleeve 24, so that the sleeve 42 ai1d plunger rod 20 may be slid inwardly from the Fig. position to'the position of Fig. 2, to contact the, tip 30 and in the construction shown in Fig. 5, this operation is done prior to actually looking the hinged head 26 in position by means of the locking sleeve 24. i

The plunger rod and cartridge tip gripping device may be made for replacement of the usual plunger in the conventional syringe of the class describedl With the locking sleeve released and slightly pivoted to make a small angle with the barrelfof' the syringe, the usual rod is removable by axially sliding it inwardly'througha barrel window, after removing, the thumb-piece 46' which is threaded on the plunger-I The new rod is thenapplied in a reverse manner. i Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than assetffo'rth in the'clainis, but what I claim is:

1. A syringe for use with a disposable ampoule cartridge having a plunger and said plunger having an exposed resilient tip extending therefrom, said "syringe comprising a barrel for receiving the cartridge, a needle'on the barrel, a hinged head on the barrel, a locking sleeve on the head, and a pliin'ger rod's'lidably mounted in the head, and means on said plunger rod for selectively gripping the cartridge plunger tipfor movement of the cartridge plunger with the plunger rod in either direction for both aspiration and injection, the plunger tip gripping means comprising a series of radiallymovable fingers on the plunger rod at the inner end thereof and includingmeans for moving said fingers radially inwardly to grip the tip, said finger moving means includes a rotatable sleeve surrounding the fingers, and means for moving the sleeve axially relative to said fingers, said fingers being resilient and extending into the path of the sleeve.

2. A syringe for use with a disposable ampoule cartridge having a plunger and said plunger having an exposed resilient tip extending therefrom, said syringe comprising a barrel for receiving the cartridge, a needle onthe barrel, a hinged head on the barrel, a locking sleeve on the head, and a plunger rod slidably mounted in the head, and means on said plunger rod for selectively gripping the cartridge plunger tip for movement of the cartridge plunger with'the plunger rod in either direction for both aspiration and injection, the plunger tip gripping means comprising a series of radially movable fingers on the plunger rod'at the inner end thereof and including means for moving said fingers radially inwardly to grip the tip wherein the means for actuating the gripping fingers comprisesa sleeve rotatable on the plunger, rod and non-rotatably associated with the hinged head locking sleeve for rotatiqn of the finger-actuating sleeve by the locking sleeve, and interengaging means between said finger actuating sleeve and the gripping fingers moving said fingers radially inwardly upon relative axial motion thereof.

FOREIGN PATENTS 620,824 Great Britain May 30, 1949 

